class Point1{
    int x,y;
    void setXY(int m,int n){
        x = m;
        y = n;
    }
}

public class Example4_4 {
    public static void main(String[] args) {
        Point1 p1,p2;
        p1 = new Point1();
        p2 = new Point1();
        System.out.println("p1的引用："+p1);
        System.out.println("p2的引用："+p2);
        p1.setXY(1111,2222);
        p2.setXY(-100,-200);
        System.out.println("p1的坐标："+p1.x+","+p1.y);
        System.out.println("p2的坐标："+p2.x+","+p2.y);
        p1 = p2;
        System.out.println("将p2的引用赋给p1后：");
        System.out.println("p1的引用："+p1);
        System.out.println("p2的引用："+p2);
        System.out.println("p1的坐标："+p1.x+","+p1.y);
        System.out.println("p2的坐标："+p2.x+","+p2.y);
    }
}
